Stop gauge for a punching apparatus



July 21, 1953 A. M. MacPHEA-r 2,646,122

sToP GAUGE FOR A PUNCHING APPARATUS Filed Nov. 21, 195o 2 sheets-sheet 1 :VIII

July 21, 1953 A, M wlacFq-"LIAT V 2,646,122

STOP GAUGE FOR A PUNCHING APPARATUS Filed Nov. 2l, 1950 2 Shets-Sheet 2 UMH i Il.

/fvVf/VTO-R AMMAC/@MEAT Patented July 2l, 1953 STOP GAUGE FR A PUNCHING APPARATUS Alexander M. MacPheat, Indianapolis, Ind., assigner to Western Electric Company, incorporated, New York, N. Y., a corporation of New York Application November 21, 1950, Serial No. 196,778

3 Claims.

This invention relates to a stop gage Afor a punching apparatus, and more particularly to f apparatus for substantially preventing formation of incomplete articles by a punch press.

In the manufacture of articles from punched strips of stock having perforations or the like in the articles, the perforations are sometimes formed at equally spaced points along a strip, and then the articles themselves are blanked out. Punch presses having automatic stops have been provided in the past for accurately positioning perforate strips in the punchpressuntil the trailing end of the strip hasv been reached, after which the strip must be fed manually with great care to prevent forming incomplete blanks. In the past there has been no automatic stops capable by themselves of minimizing formation of incomplete articles at the trailing end of a strip. j

An object of the invention is to provide new and improved apparatus for feeding strips of stock into punch presses.

f A further object of the invention is to provide a new and improved apparatus for substantially preventing the formation of incomplete articles fromv strips being fed into punchv presses.

Another object of the invention is to provide means lfor latching an automatic stop` in inoperative position in a punch press set ata point of feeding of strip through the punch press at which an incomplete blank would be formed in the next operation of the punch press.

An apparatus illustrating certain features of the invention for substantially preventing formation of incomplete blanks from stock may include a punch press having an automatic stop device engageable with the stock as the stock is fed forward after a blank has been formed to position the stock for the succeeding blanking operation. stock guide Ymember for orientingY the stock transversely, means for latching the automatic stop device in inoperative position and means operable by the stock guide after the trailing end of the stock has been moved past the stock guide for actuating the latch to hold the automatic stopdevice in inoperative position.

A complete understanding of the invention may be obtained by thev following detailed description of an apparatus forming a specific embodiment thereof, when read in conjunction with the appended drawings, in which A Fig. 1 is a fragmentary, side elevationai View of an apparatus forming one embodiment of the This apparatus also may include aV 2 invention with a strip of material to be punched in one position;

Fig. 2 is a fragmentary, horizontal section of a portion of the apparatus taken along line 2--2 of Fig. 1;

Fig. 3 is a side, elevational view similar to that shown in Fig. 1 with the strip being punched at a different stage in the punching operation of the strip, and Y Fig. 4 is a fragmentary, horizontal section taken along line L -ll of Fig. 3.

Referring now in detail to the drawings, there is shown therein a punch press for punching rectangular articles from a stock strip ill which has holes l2-l2 previously punched therein at equally spaced points along 4the length of the strip.v yThe punch press includes a reciprocable platen ill continuously reciprocated toward and away from a stationary platen IS. A punch I8 cooperates with a die 20 to punch rectangular articles from the stock strip lil, which must be so positioned that pilot pins 22-22 enter the holes l2-l2 to accurately locate the stock strip I0 just before each blank is punched therefrom. The strip l@ is pulled manually along a guideway24 formed between the upper surface of the die Ziand a stripper plate 26 to position between each punching operation of the punch press.

A lever 30 mounted pivotally on a pin 3l has a stop arm 32 designed to project through a large hole 34 formed in the stripper plate 26 into the plane of the stock strip Hl. A spring 3l urges the lever in a clockwise direction, as viewed in Fig. 1, and also urges the lever in a clockwise direction, as viewed in Fig. 2. The stop arm 32 is designed to be engaged by an edge 38 formed on the strip by the preceding punching operation as the strip lil is pulled manuallyv to the left, as viewed in Fig. 2. The strip pulls the lever 30 to a position in which the lever engages the lefthand wall of a slot 39 formed in' thel stripper plate 2S into which the lever it ts loosely. ln this position, the holes Ell-i2 are in correct positions to receive the pilot pins 22-22 and-the strip il! is in substantially correct position for the succeeding punch operation.

A stock guide v4l having a sloping edge l2 mounted slidably in the guideway i3 formed in the stripper plate 26 is urged against the trailingend of thefstrip l0 by a latch llt, which is pressed by a leaf spring 47 in a clockwise direc# tion, as viewed in Fig. 1. The strip lil normally .holds the guide 4l in a position in which the latch 4S is held out of engagement with a cam surface 49 formed on the lever 30. But when the trailing end of the stock strip goes past the guide 4l, the spring 41 presses the latch 46 and the guide 4I toward the positions thereof shown in Fig. 4, which position the latch will assume the next time the stop lever is pivoted. When the latch is in this position it latches the arm 3l] in a position in which the stop pin 32 is held upwardly out of the plane of the strip l. A spring actuator 50 mounted on the punch press engages the lever 30 after the pilot pins 22 have entered the holes l2--l2 and pivots the lever 30 to a position in which the stock pin 32 is withdrawn completely from the plane of the strip l0.

Operation The stock strip I manually is urged constantly along the guideway 24 to the left, as viewed in Fig. 2, and the edge 38 is held against the stock pin 32. The reciprocable platen I4 then is moved downwardly toward the stock strip, the pilot pins 22-22 enter the holes l2-I2 and accurately locate the stock strip between the punch and the die, the spring 59 engages the lever 3l) and pivots it to a position in which the stop pin 32 is lifted out of the plane of the stock strip, and the punch lli punches a rectangular blank from the strip. Then the reciprocable platen I4 is moved away from the stationary platen I6, and, when the stop pin 32 is lifted out of the plane of the stock strip, the spring 31 urges it in a clockwise direction, against the righthand wall of the slot 39 to a position in which the pin overlaps the edge 33. Then the reciprocable platen is retracted, the pins 22-22 move out or the article, the die IS moves out of the plane of the strip and the actuator 56 moves away from the lever 30. The spring 31 urges the lever 30 in a clockwise direction, as viewed in Fig. l, but the stop pin 32 engages the top of the stock and is prevented thereby from entering the just formed opening in the stock until the stock is pulled to left, as viewed in Fig. 2, which the operator then does manually. As the stock strip is so pulled, the opening just formed by the punch I8 is pulled under the pin 32 and the pin drops into that opening. The pulling of the stock is continued until the trailing edge of the newly formed opening in the stock strip engages the stock and swings the lever 30 against the lefthand wall of the slot 39.

The operation just described is repeated until the stock strip is almost completely punched out and the trailing end of the strip has just been moved past the guide 4I with insuicient stock between the lefthand edge of the guide 4| and the die to form another article. Then, when the punch press punches the last possible complete article from the strip, and the actuator 58 moves the lever 30 to the position in which it is shown in Fig. 3, the spring 41 presses the latch 46 under the righthand arm of the lever 30 and latches the lever 3G in its retracted position. Hence, on retraction of the reciprocable platen away from the stationary platen, the stop pin 32 will not be moved into the plane of the strip I3 and the manual pull on the strip pulls the trailing end of the strip completely out of the press before the next downward movement of the reciprocating platen occurs. A new strip to be punched out then is inserted into the punch press, engagesthe beveled edge 42 of the guide 4|, pushes it from the position in which it is shown in Fig. 4 to the position in which it is shown in Fig. 2, which moves the guide to the left as viewed in Fg- 3, and

moves the latch 4B out of engagement with the lever 30 to permit the spring 31 to urge the lever to a stock stopping position.

The reciprocable platen may be continuously and automatically reciprocated with minimum danger of forming incomplete blanks from the trailing end of the strips, because the automatic stop device is held in an inoperative position during the feed of the strip which would place the trailing end of the strip between the punch and die if the automatic stop device were permitted to operate.

It is to be understood that the above-described arrangements are simply illustrative of the application of the principles of the invention. Numerous other arrangements may be readily devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof.

What is claimed is:

l. In a punch press including a pair of cooperable relatively movable die elements, means for moving the die elements together and apart, means for guiding a strip from which articles are to be punched across one of the die elements, a stop operable by and designed to enter an opening in the strip formed by the die elements to limit travel of the strip, the combination therewith of a latch for maintaining the stop in an inoperable position, means for actuating the latch7 and a feeler associated with the guideway operable while in engagement with the strip for holding the latch-actuating means inoperative.

2. A punch press, which comprises a stationary platen, a die mounted on the stationary platen, a reciprocable platen movable toward and away from the stationary platen, a punch having a pilot pin carried by the reciprocable platen, a guideway on the stationary platen extending across the die for guiding a strip having holes therein across the die, a stop pin at the recess side of the die movable between an inoperative position away from the strip and an operative position projecting into an opening punched in the strip by punch and the die to stop advancement of the strip in a position in which one of the holes in the strip is aligned with the pilot pin, means urging the stop pin toward its operative position, means carried by the movable platen for moving the stop pin to its inoperative position after the pilot pin has entered the hole in the strip aligned therewith, a presser mounted at a predetermined point on the approach side of the guideway in the plane of the guideway and reciprocable transversely thereto with respect to the guideway, means urging the presser into the guideway against the unpunched portion of the strip, and a cam movable by the presser-urging means to a position'holding the stop pin in its inoperative position when the trailing end of the strip clears the presser and the stop pin has been moved to its inoperative position.

3. A punch press, which comprises a stationary platen, a die mounted on the stationary platen, a reciprocable platen movable toward and away from the stationary platen, a punch carried by the reciprocable platen, a guideway on the stationary platen for guiding a strip having holes therein across the die and holding the strip against the die, a stop pivotable between an inoperative position away from the strip and an operative position projecting into an opening punched in the strip and the die to stop advancement of the strip in a position to have another the guideway and extending transversely with re'- spect thereto, means urging the presserl into the guideway against the unpunched portion of the strip, and a latch movable by the presser-urging 6 means to a position holding the stop in its inoperative position When the trailing end of the Vstrip clears the presser and the stop has been moved to its inoperative position.

ALEXANDER M. MACPHEAT.

References Cited in the file of this patent UNITED STATES PATENTS o Number Name Date 1,538,440 Linnen i May 19, 1925 1,619,214 olgay Mar. 1, 1927 2,219,060 West oct. 22, 195o 

